A slide-fastener stringer half is known having a coupling element formed as a synthetic-resin monofilament with a longitudinal succession of turns each having a pair of shanks connected together by a coupling head, with one of the shanks of each turn connected via a bight to a shank of an adjoining turn. It is known to lay these shanks directly into a knit support tape so that the coupling element itself forms part of the knit and stitching is not necessary to secure the stringer half together. In such an arrangement the coupling head extends laterally beyond one of the longitudinal edges of the support tape (see Japanese patent JA-PS No. 38-11 673).
In some arrangements the two shanks of each turn are knitted into adjacent but succeeding and separate courses of the knitted support tape. The coupling heads joining the two shanks of each turn project laterally from a longitudinal edge of the tape and lie in a plane which extends generally perpendicular to the tape. This perpendicular position is necessary in order to prevent the slide-fastener formed with such a stringer from opening accidently (see German open application DT-OS No. 22 21 325).
It has also been suggested to knit both of the shanks into a single course. This makes the manufacture of the coupling tape extremely difficult with conventional warp-knitting machines. Complicated control mechanisms are invariably required. The main difficulty is that when a coupling element made from a synthetic-resin monofilament of normally around 0.5 mm diameter is knitted into the tape it is not possible readily to conform the course locations to the gauge (head spacing) of the coupling element so that such a coupling-element coil can be knitted into each course.